G. M. Light, C. Thwing, A. R. Puchot, Southwest Research Institute, San Antonio, TX
The DoD aircraft fleets consisting of the C-5, C-17, B-52, A-10, F-16, F-15, and others are aging and in many cases either exceeding their intended life or rapidly approaching their intended life with no new aircraft purchases on the horizon. One way to keep the aircraft flying is to use structural health monitoring (SHM) technologies. SwRI has developed the magnetostrictive sensor (MsS) technology that has been successfully used to monitor piping, but has applications to plate geometries such as aircraft structure. The MsS probe has a low profile (approximately 0.005 inch thick) and is bonded to the surface of the structure. The MsS probe generates a guided wave that travels long distances from the probe into the plate or aircraft structure to provide a means of long range inspection and condition monitoring. SwRI has conducted a wide range of laboratory tests to demonstrate the feasibility of MsS to detect defects under fasteners, quality of bond of patches, and defect growth under patches. Recently, SwRI utilized the MsS technology on a C-141 test panel. The MsS was bonded to various surfaces and then the surfaces were subjected to 20,000 ksi loads to study potential issues associated with sensor debonding and slight changes that might occur in the fastener holes. Notches were introduced into several fastener holes and used the MsS to monitor changes in the defects. The purpose of this paper is to describe the MsS technology and the results of the various laboratory experiments showing the potential for MsS aircraft structural health monitoring. The DoD aircraft fleets consisting of the C-5, C-17, B-52, A-10, F-16, F-15, and others are aging and in many cases either exceeding their intended life or rapidly approaching their intended life with no new aircraft purchases on the horizon. One way to keep the aircraft flying is to use structural health monitoring (SHM) technologies. SwRI has developed the magnetostrictive sensor (MsS) technology that has been successfully used to monitor piping, but has applications to plate geometries such as aircraft structure. The MsS probe has a low profile (approximately 0.005 inch thick) and is bonded to the surface of the structure. The MsS probe generates a guided wave that travels long distances from the probe into the plate or aircraft structure to provide a means of long range inspection and condition monitoring. SwRI has conducted a wide range of laboratory tests to demonstrate the feasibility of MsS to detect defects under fasteners, quality of bond of patches, and defect growth under patches. Recently, SwRI utilized the MsS technology on a C-141 test panel. The MsS was bonded to various surfaces and then the surfaces were subjected to 20,000 ksi loads to study potential issues associated with sensor debonding and slight changes that might occur in the fastener holes. Notches were introduced into several fastener holes and used the MsS to monitor changes in the defects. The purpose of this paper is to describe the MsS technology and the results of the various laboratory experiments showing the potential for MsS aircraft structural health monitoring.
Summary: SwRI has developed the magnetostrictive sensor (MsS) technology that has been successfully used to monitor piping, but has applications to plate geometries such as aircraft structure. The MsS probe has a low profile (approximately 0.005 inch thick) and is bonded to the surface of the structure. The MsS probe generates a guided wave that travels long distances from the probe into the plate or aircraft structure to provide a means of long range inspection and condition monitoring. SwRI has conducted a wide range of laboratory tests to demonstrate the feasibility of MsS to detect defects under fasteners, quality of bond of patches, and defect growth under patches.
